1. Field of the Invention
This invention relates to an elevator cage, and more particularly to an elevator cage which can reduce the vibration transmitted to a cage chamber.
2. Description of the Related Art
FIG. 8 is an explanatory view showing one example of a conventional elevator cage and shows the state of an elevator cage guided by guide rails suspended in the hoistway.
In FIG. 8, a cage frame 2, of which details are omitted here, composing an elevator cage 1 is suspended by a main rope 5 between a pair of guide rails 6 formed in the T-shaped section that are provided vertically on the inner wall surfaces of the hoistway.
On a lower beam 2a at the lower end of age frame 2, four rubber vibration isolators 4 are fixed. A cage chamber 3, of which details are omitted here, is placed on rubber vibration isolators 4 in such a way that on the upper surfaces of rubber vibration isolators 4 the cage floor at the lower end of cage chamber 3 is placed.
There are rubber vibration isolators 7, of which details are omitted here, mounted symmetrically between the upper sides of cage chamber 3 and vertical beams 2b of cage frame 2, respectively.
At the left and right of the upper and lower ends of cage frame 2, guide rollers 8 are mounted symmetrically and are kept in contact with both sides and the top of guide rails 6, respectively. At the center of an upper beam 2c of cage frame 2, a main rope fixing bar (not shown) is penetrating upper beam 2c, and the lower end of main rope 5 is connected to the top end of this main rope fixing bar.
The upper end of main rope 5 is wound round a lifting wheel of a hoist (not shown) installed in a machine room formed on the top of the hoistway and then, hang down the hoistway. A balance weight (not shown) is attached to and is suspended from the other lower end of main rope 5.
In elevator cage 1 in this structure, the vibration is transmitted to lower beam 2a from guide rollers 8 rotating on guide rails 6. In order to reduce the vibration transmitted to cage chamber 3 from lower beam 2a, rubber vibration isolators 4 are incorporated into cage frame 2.
There are various causes for guide rollers 8 to vibrate, for instance, a slight difference in levels at the connecting portions of guide rails 6, slight meanders of guide rails 6. The vibration from a hoist that is transmitted from main rope 5 etc. is also transmitted to cage frame 2.
Therefore, rubber vibration isolators 4 are provided between lower beam 2a and the cage floor, and rubber material is also used for rubber vibration isolators 7 and guide rollers 8, thereby to reduce uncomfortable riding feeling of cage passengers.
For elevator cage 1 in such structure as described above, in particular, for elevator of which speed is accelerated at higher head, it is demanded to improve more comfortable riding quality by further reducing vibration transmitted to cage chamber 3.